This paper uses the GEM-E3 macroeconomic computable general equilibrium model to calculate the magnitude of greenhouse gas (GhG) emission rebound effects across a range of efficiency scenarios in the automotive sector supply chain. The scenarios are technically feasible as they are designed using bottom up information from the iron and steel industry. Rebound effects occur when efficiency improvements reduce prices, stimulating demand and offsetting some of the environmental benefits that would otherwise be had. This paper allows energy, material and product-service efficiency rebound effects to be compared for the first time. The results suggest that there is a greater risk of rebound effects for downstream emissions abatement strategies that save embodied emissions: 85% of the emissions savings in the product-service efficiency scenario and 77% of emissions in the material efficiency scenario are offset by economy-wide rebound effects. This compares to 7% in the energy efficiency scenario. These findings show that, in the current policy environment in which GhG emissions remain relative unconstrained, improvements in material efficiency that are particularly good at spurring growth are also likely to carry the greatest rebound effects. The conclusions of this paper are not purely dependent on the chosen macroeconomic model, but are a function of the underlying value structure along supply chains: downstream efficiency improvements that save embodied emissions involve greater potential monetary savings per unit GhG avoided, spurring rebound effects.

中文翻译：

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比较能源和材料效率的反弹效应：探索 GEM-E3 宏观经济模型中的情景

本文使用 GEM-E3 宏观经济可计算一般均衡模型来计算汽车行业供应链中一系列效率情景中温室气体 (GhG) 排放反弹效应的大小。这些场景在技术上是可行的，因为它们是使用来自钢铁行业的自下而上的信息设计的。当效率的提高降低了价格、刺激了需求并抵消了一些本来可以带来的环境效益时，就会出现反弹效应。本文首次对能源、材料和产品服务效率的回弹效应进行了比较。结果表明，降低隐含排放量的下游减排战略存在更大的反弹效应风险：产品服务效率情景中 85% 的减排量和材料效率情景中 77% 的排放量被经济范围内的反弹效应抵消。相比之下，在能效情景中为 7%。这些调查结果表明，在温室气体排放相对不受约束的当前政策环境中，特别擅长刺激增长的材料效率提高也可能带来最大的反弹效应。本文的结论并不完全取决于所选择的宏观经济模型，而是取决于供应链中潜在价值结构的函数：下游效率改进可减少隐含排放量，每避免单位温室气体排放量可能会节省更多资金，从而刺激反弹效应。